How to format your references using the Constraints citation style

This is a short guide how to format citations and the bibliography in a manuscript for Constraints. For a complete guide how to prepare your manuscript refer to the journal's instructions to authors.

Using reference management software

Typically you don't format your citations and bibliography by hand. The easiest way is to use a reference manager:

PaperpileThe citation style is built in and you can choose it in Settings > Citation Style or Paperpile > Citation Style in Google Docs.
EndNoteFind the style here: output styles overview
Mendeley, Zotero, Papers, and othersThe style is either built in or you can download a CSL file that is supported by most references management programs.
BibTeXBibTeX syles are usually part of a LaTeX template. Check the instructions to authors if the publisher offers a LaTeX template for this journal.

Journal articles

Those examples are references to articles in scholarly journals and how they are supposed to appear in your bibliography.

Not all journals organize their published articles in volumes and issues, so these fields are optional. Some electronic journals do not provide a page range, but instead list an article identifier. In a case like this it's safe to use the article identifier instead of the page range.

A journal article with 1 author
Gottfried, K. (2000). Inferring the statistical interpretation of quantum mechanics from the classical limit. Nature, 405(6786), 533–536.
A journal article with 2 authors
Sun, Z.-W., & Allis, C. D. (2002). Ubiquitination of histone H2B regulates H3 methylation and gene silencing in yeast. Nature, 418(6893), 104–108.
A journal article with 3 authors
Ryugo, D. K., Kretzmer, E. A., & Niparko, J. K. (2005). Restoration of auditory nerve synapses in cats by cochlear implants. Science (New York, N.Y.), 310(5753), 1490–1492.
A journal article with 8 or more authors
Honma, S., Kawamoto, T., Takagi, Y., Fujimoto, K., Sato, F., Noshiro, M., … Honma, K.-I. (2002). Dec1 and Dec2 are regulators of the mammalian molecular clock. Nature, 419(6909), 841–844.

Books and book chapters

Here are examples of references for authored and edited books as well as book chapters.

An authored book
Marcus, Y. (2012). Supercritical Water. Hoboken, NJ: John Wiley & Sons, Inc.
An edited book
Dinklage, A., Klinger, T., Marx, G., & Schweikhard, L. (Eds.). (2005). Plasma Physics: Confinement, Transport and Collective Effects (Vol. 670). Berlin, Heidelberg: Springer.
A chapter in an edited book
Payne-James, J. J., Payne-James, J. J., & Hinchliffe, J. (2011). Injury Assessment, Documentation, and Interpretation. In M. M. Stark (Ed.), Clinical Forensic Medicine: A Physician’s Guide (pp. 133–167). Totowa, NJ: Humana Press.

Web sites

Sometimes references to web sites should appear directly in the text rather than in the bibliography. Refer to the Instructions to authors for Constraints.

Blog post
Hale, T. (2016, July 6). This Cricket Was Infested By “Mind Controlling” Worms. IFLScience. IFLScience. Retrieved October 30, 2018, from


This example shows the general structure used for government reports, technical reports, and scientific reports. If you can't locate the report number then it might be better to cite the report as a book. For reports it is usually not individual people that are credited as authors, but a governmental department or agency like "U. S. Food and Drug Administration" or "National Cancer Institute".

Government report
Government Accountability Office. (1982). NASA Must Reconsider Operations Pricing Policy To Compensate for Cost Growth on the Space Transportation System (No. MASAD-82-15). Washington, DC: U.S. Government Printing Office.

Theses and dissertations

Theses including Ph.D. dissertations, Master's theses or Bachelor theses follow the basic format outlined below.

Doctoral dissertation
Ross, T. A. (2008). The surgical technologist learning partnership: A comparison of factors in a preceptor relationship (Doctoral dissertation). University of Phoenix, Phoenix, AZ.

News paper articles

Unlike scholarly journals, news papers do not usually have a volume and issue number. Instead, the full date and page number is required for a correct reference.

New York Times article
Kelly, M. (1993, June 6). Clinton Myth of Nonideological Politics Stumbles. New York Times, p. 126.

In-text citations

References should be cited in the text by sequential numbers in square brackets:

This sentence cites one reference [1].
This sentence cites two references [1, 2].
This sentence cites four references [1–4].

About the journal

Full journal titleConstraints
ISSN (print)1383-7133
ISSN (online)1572-9354
ScopeArtificial Intelligence
Computational Theory and Mathematics
Discrete Mathematics and Combinatorics

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